FIBER PRODUCT PROCESSING METHOD

Abstract: A textile treatment method for providing a textile with water- and oil-repellency by treating a textile with a salt of metal having a valency of at least two, and then treating the textile with hydrophilic functional group-containing fluoropolymer capable of coordinating with that metal, can stably provide the textile with high initial water- and oil-repellency and high permanent water- and oil-repellency.

Description: FIELD OF THE INVENTION The present invention relates to a method for treating a textile. Particularly, it relates to a textile treatment method which can give excellent initial water- and oil-repellency and excellent durable water- and oil-repellency when a textile, especially a hydrophilic textile is treated for modification. RELATED ART Hitherto, it is known that a fluorine-containing compound has an excellent property of a water- and oil-repellent. Particularly, a treatment agent comprising a polymer of a fluoroalkyl group-containing vinyl monomer has been practically used. Such polymer is sometimes a homopolymer of a fluoroalkyl group-containing vinyl monomer. In many cases, it is a copolymer with various fluorine-free vinyl monomers. The used fluorine-free vinyl monomers include a hydrophilic monomer. For example, Japanese Patent Kokoku Publication JP-B-62047466 discloses a water- and oil repellent comprising a phosphoric acid group-containing monomer and a perfluoroalkyl group-containing vinyl monomer. However, the use of the copolymer with the hydrophilic vinyl monomer such as the phosphoric acid group-containing monomer gives poor adhesion to a hydrophilic textile such as nylon because of an electrical charge of the polymer from an electrical property of functional group and a hydrophilic property of the polymer, and sometimes gives no water- and oil-repellency. FR-A-2270364 discloses a method for treating hydrophilic fibrous textile materials comprising the treatment of fibrous materials in a bath containing (a) a salt of the 2 to 4 valent metal and (b) a fluorine containing polymer. This fluorine containing polymer comprises moieties of a monomer containing fluoroalkyl groups of the formula X-C a F 2a wherein X is H or F and a is 4 to 14, and a moiety representing phosphoric acid ester salt and/or an oxyalkylation reaction product moiety which may comprise a sulfuric acid ester group. US 3467612 concerns a textile treated composition containing fluorinated acrylic polymers together with polyvalent metal salts of weak acids. According to the method described therein the fibrous material is treated with a metal salt of (in)organic acid and subsequently with a water-repellent copolymer of perfluoroalkyl(meth)acrylate and an ethylenically unsaturated monomer. SUMMARY OF THE INVENTION An object of the present invention is to give excellent initial water- and oil-repellency and excellent durable water- and oil-repellency to a textile, particularly a hydrophilic textile due to the stabilized exhibition of water- and oil-repellency of a fluorine-containing polymer. According to one aspect, the present invention provides a method for treating a textile, comprising treating the textile with a salt of a metal having a valency of at least two and then treating the textile with a fluorine-containing polymer having a hydrophilic functional group selected from a phosphoric acid group and a sulfonic acid group capable of coordinating with said metal. According to another aspect, the present invention provides a textile treated by the above treatment method. DETAILED EXPLANATION OF THE INVENTION The term "treatment" used in the present specification means that the textile is contacted with a treatment liquid containing the metal salt or the fluorine-containing polymer. The "treatment" includes a dip process, an impregnation process, a padding process, and a coating process. The hydrophilic functional group is preferably selected from the group consisting of a phosphoric acid group and a sulfonic acid group. The fluorine-containing polymer is preferably a copolymer having (a) a repeating unit derived from a fluorine-containing vinyl monomer, (b) a repeating unit derived from an acid group-containing monomer of the formula: wherein R 1 is a hydrogen atom or a methyl group, R 2 is a non-substituted or substituted alkylene group having at most 6 carbon atoms, or a divalent group in which the above alkylene group is bonded to an ether group, an ester group, an amide group and the like, X is PO or SO 2 , M is a hydrogen atom or an alkaline metal atom, p is 1, n and m are 1 or 2 and n + m = 3 when X is PO, and p is 0 and n = m = 1 when X is -SO 2 -, and (c) optionally present, a repeating unit derived from a fluorine-free monomer containing none of the phosphoric add group and the sulfonic acid group (the total amount of the components (b) and (c) is at most 100 parts by weight per 100 parts by weight of the component (a)). The fluorine-containing vinyl monomer (a) is a compound having both of a polyfluoroalkyl group (particularly a perfluoroalkyl group) or a polyfluoroalkenyl group (particularly a perfluoroalkenyl group) and a polymerizable unsaturated double bond (particularly a carbon-carbon double bond). Specific examples of the fluorine-containing vinyl monomer (a) are following compounds: wherein R 11 is a hydrogen atom or a methyl group, R 12 is a lower alkyl group, X is a divalent organic group, m is an integer of 1 to 4, and n is an integer of 5 to 21. The carbon number of R 12 is usually from 1 to 6. Examples of X are a C 1 -C 10 alkyleneoxy group, an oxygen atom, a sulfur atom, an amino group optionally substituted with a C 1 -C 6 lower alkylene group and the like. The acid group-containing monomer (b) has an anionic functional group capable of coordinating with the metal. The functional group is a phosphoric acid group or a sulfonic acid group. Specific examples of the acid group-containing monomer (b) are the following compounds: mono(2-hydroxyethylacrylate) acid phosphate, mono(2-hydroxyethylmethacrylate) acid phosphate, mono(2-hydroxypropylacrylate) acid phosphate sodium salt, mono(3-hydroxypropylmethacrylate) acid phosphate, mono(allylalcohol) acid phosphate, mono(3-chloro-2-hydroxypropylmethacrylate) acid phosphate, mono(2-hydroxyethylvinylether) acid phosphate, mono(3-hydroxypropylmethacrylamide) acid phosphate, (2-hydroxyethylacrylate) acid phosphate, 2-acrylamido-2-methylpropane sulfonic acid, 2-methacrylamido-2-ethylpropane sulfonic acid, 2-acrylamido-butanesulfonic acid, 2-(acrylcarbonyloxy)ethylsulfonic acid, and the like. The copolymerization ratio of the fluorine-containing vinyl monomer (a) to the acid group-containing monomer (b) is in a range giving no adverse effect on the water- and oil-repellency. The amount of the acid group-containing monomer (b) is usually at most 50 parts by weight, preferably from 0.2 to 30 parts by weight per 100 parts by weight of the fluorine-containing vinyl monomer (a). The fluorine-containing polymer may contain at least one fluorine-free monomer (c) having neither of the phosphoric acid group nor the sulfonic acid group. The amount of the fluorine-free monomer (c) is usually smaller than 100 parts by weight, preferably from 0 to 50 parts by weight per 100 parts by weight of the fluorine-containing vinyl monomer (a). Specific examples of the fluorine-free monomer (c) are a lower olefinic halogenated or non-halogenated hydrocarbon such as ethylene, propylene, isobutene, 3-chloro-1-isobutene, butadiene, isoprene, chloro- and dichloro-butadiene, 2,5-dimethyl-1,5-hexadiene and diisobutylene; a vinyl, allyl or vinylidene halide compound such as vinyl chloride or vinylidene chloride, vinyl fluoride or vinylidene fluoride, and ally bromide or methallyl chloride; styrene and a styrene derivative such as vinyltoluene, α-methylstyrene, α-cyanomethylstyrene, divinylbenzene and N-vinylcarbazole; a vinyl ester such as vinyl acetate, vinyl propionate, a vinyl ester of acid known as trade name "Versatic acids", vinyl isobutyrate, vinyl senecioate, vinyl succinate, vinyl indecanoate, vinyl stearate and divinyl carbonate; an ally aster such as allyl acetate and heptanoate; a halogenated or non-halogenated alkyl vinyl or alkyl allyl ether such as cetyl vinyl ether, dodecyl vinyl ether, isobutyl vinyl ether, ethyl vinyl ether, 2-chloroethyl vinyl ether and tetraallyloxyethane; a vinyl alkyl ketone such as vinyl methyl ketone; an unsaturated acid such as acrylic acid, methacrylic acid, α-chloroacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid and senecioic acid; an anhydride thereof and an ester thereof, for example, a vinyl, allyl, methyl, butyl, isobutyl, hexyl, heptyl, 2-ethylhexyl, cyclohexyl, lauryl or stearyl ester, or 2-isocyanatoethyl acrylate and methacrylate, dimethyl maleate, ethyl crotonate, monomethyl maleate, monobutyl itaconate, a diacrylate and dimethacrylate of glycol and polyalkylene glycol such as ethyleleglycol or triethyleneglycol dimethacrylate, and methacryloyloxypropyltrimethoxysilane; an alkyl cyanoacrylate such as isopropyl cyanoacrylate, acrylonitrile, methacrylonitrile, 2-chloro-acrylonitrile, 2-cyanoethylacrylate or methacrylate, methyleneglutaronitrile, vinylindenecyanide, trisacryloyl-hexahydro-s-triazine, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane and N-vinyl-2-pyrrolidone; hydroxyalkyl acrylate and methacrylate such as ethyleneglycol monoacrylate and propyleneglycol monomethacrylate, acrylate and methacrylate of polyalkyleneglycol, allyl alcohol, allyl glycolate, isobutene diol, allyloxyethanol, o-allylphenol, divinylcarbinol, glycerine-α-allylether, acrylamide, methacrylamide, maleamide, maleimide, N-(cyanoethyl)-acrylamide, N-isopropylacrylamide diacetoneacrylamide, N-(hydroxymethyl)-acrylamide, N-(hydroxymethyl)-methacrylamide, N-(alkoxymethyl)-acrylamide, N-(alkoxymethyl)-methacrylamide, glyoxalbisacrylamide, sodium acrylate or methacrylate, vinylsulfonic acid, styrene-p-sulfonic acid, alkaline metal salt thereof, 3-aminochrotonenitrile, monoallylamine vinylpyrridine, glycidyl acrylate or methacrylate, allyl glycidyl ether, acrolein, N,N-dimethylaminoethyl or N-tert.-butylaminoethylmethacrylate. The method for preparing the fluorine-containing polymer is not limited and may be a conventionally used solution polymerization, emulsion polymerization or the like. A radical initiator may be used for the polymerization. The molecular weight of the fluorine-containing polymer used in the present invention is usually from 1,000 to 1,000,000. The metal salt treatment means that the textile is dipped in a liquid containing the salt of metal having the valency of at least two, and it is used as the first step in the method of the present invention. Preferable examples of the metal are chromium, zirconium, titanium, aluminum and the like. Preferable examples of the metal salt are a sulfate salt, a nitrate salt, a chloride and the like. Among them, basic chromium sulfate is recommendable, since it has a particularly strong strength of bonding to an anionic functional group. In a preferable embodiment of the present invention, the textile is dipped in a liquid containing the metal salt (the liquid temperature: 20-70°C), a pH value of the liquid is optionally adjusted to a range between 5 and 7, preferably between 5.5 and 6.5 and then the textile is washed with water. The metal salt liquid is an aqueous solution or aqueous suspension containing 0.01 to 50 % by weight, preferably 0.5 to 10 % by weight, based on the weight of the textile, of the metal salt. The time for dipping the textile is usually at least 10 seconds, preferably from 1 minute to 120 minutes. The pH adjustment can be conducted by using sodium acetate, sodium formate, sodium hydrogen carbonate and the like. Then, the dried textile is treated with the fluorine-containing polymer. The treatment with the fluorine-containing polymer is a second step in the present invention. Said treatment may be a conventionally conducted process, for example, an impregnation process, a padding process, a coating process and the like. Then, the textile is dried. After the treatment with the metal salt, the textile can be treated with the fluorine-containing polymer in the same bath. In such case, after the metal salt treatment, the pH adjustment and the washing with water, the fluorine-containing polymer in the amount of 0.01 to 50 % by weight, preferably 5 to 25 % by weight in solid, of the textile weight is added to the bath and textile is dipped for at least 10 seconds, preferably 1 minute to 120 minutes. The use of the fluorine-containing polymer neutralized with an organic base such as ammonia and triethylamine, or an inorganic base such as sodium hydroxide and potassium hydroxide is particularly effective on the treatment of the textile having a large thickness. In the case of use of the neutralized fluorine-containing polymer, after the textile is dipped, a 0.1 to 5 % aqueous solution of a mineral acid such as hydrochloric acid and sulfuric acid or an organic acid such as formic acid, acetic acid and propionic acid is preferably added to the bath so as to adjust the pH value of the bath to a range between 1 and 4, more preferably between 2.5 and 3.5. After the washing with water and the hydroextraction, the same treatment procedure as in a conventional fluorine-containing water- and oil-repellent is used. The weight ratio of the metal salt and the fluorine-containing polymer is usually from 1:10 to 10:1. The fluorine-containing polymer may be used together with various combination agents. Specific examples of the combination agent are a melamine resin, a urea resin, a blocked isocyanate, glyoxal and the like. If necessary, a thermal treatment and/or a calendaring process may be conducted. A treatment agent other than a fluorine-containing compound, for example, a silicone compound may combined. The textile treated with the metal salt/fluorine-containing copolymer according to the present invention may be treated with other water- and oil-repellent, preferably a fluorine-containing water- and oil-repellent. A homopolymer or copolymer of a fluorine-containing monomer having no anionic functional group is preferable for the improvement of the textile durability. The treated textile includes one in the form of a fiber, and a yarn, a woven fabric, a knitted fabric, a non-woven fabric and the like prepared from the fiber. Examples of the fiber are a natural fiber such as cotton, wool and silk; and a chemical fiber including a synthetic fiber such as acryl, a polyamide, a cellulose and a polyester. A textile blend of the natural fiber and the synthetic fiber may be used. The textile is preferably hydrophilic. Particularly preferable examples of the hydrophilic textile are a polyamide and a polyester. The woven fabric and artificial leather comprising a recently remarkably developed ultra-thin fiber are a preferable textile. The ultra-thin fiber has usually at most 1 Denier, preferably 1 to 0.0001 Denier, more preferably 0.1 to 0.001 Denier. EXAMPLES The present invention will be illustrated by the following Examples and Comparative Examples. The water repellency shown in Examples and Comparative Examples is determined according to JIS-L-1092-1977, and is indicated by the numeral figure shown in Table 1. The oil repellency is determined by, according to AATCC-TM-118-1966, dropping several drops of the following test solutions having different surface tensions shown in Table 2, and observing the penetration state of the drops after 30 seconds, and the maximum value of oil repellency of the test solution having no penetration is expressed as the oil repellency. Water repellency State 100 No wet on the surface 90 Slight wet on the surface 80 Partial wet on the surface 70 Wet on the surface 50 Wet over the whole surface 0 Complete wet on the front and back surfaces Oil repellency Surface tension (µN/cm (dyne/cm), 25°C) Test solution 0 Inferior to 1 1 314.5 (31.45) Nujol 2 296 (29.6) Nujol/n-Hexadecane (65/35 by volume) 3 273 (27.3) n-Hexadecane 4 263.5 (26.35) n-Tetradecane 5 247 (24.7) n-Dodecane 6 235 (23.5) n-Decane 7 214 (21.4) n-Octane 8 197.5 (19.75) n-Heptane The wash durability was measured according to JIS-L-0217-103 and is shown by the water repellency and oil repellency before and after the ten times of washing. The suffix "+" to the numeral value in the water repellency and oil repellency represents that the performance is slightly better than said numeral value and the suffix "-" to the numeral value represents that the performance is slightly worse than said numeral value. Preparative Example 1 (Preparation of fluorine-containing copolymer) A mixture consisting of a fluorine-containing vinyl monomer (Structure a) (90.2 g), a fluorine-free monomer of 2-ethylhexyl methacrylate (trade name: Light Ester EH (manufactured by Ippousha Yushi Co., Ltd.)) (10.25 g), an acid group-containing monomer of (2-hydroxyethyl acrylate) acid phosphate (trade name: Light Ester PM (manufactured by Ippousha Yushi Co. Ltd.)) (2.05 g), laurylmercaptane (0.1 g), polyoxyethyleneoctylphenylether (trade name: HS-220 (manufactured by Nippon Oil & Fats Co., Ltd.) (6.23 g), deionized water (170.8 g) and acetone (36.75 g) was emulsified in a homogenizer for one minute, and in an ultrasonic emulsifier for five minutes. The resultant emulsion was transferred to a four-necked flask. Azobisisobutylamidine hydrochloride (0.51 g) was added to the emulsion, the vapor atmosphere was replaced with the nitrogen gas and the polymerization was conducted at 55°C for 5 hours. The resultant emulsion was diluted with the deionized water (229.8 g) to give a fluorine-containing copolymer emulsion having a solid content of 20%. Structure a: (a mixture of compounds in which n is 3, 4, 5 and 6 in a molar ratio of 5:3:2:1) Preparative Examples 2 to 4 (Preparation of fluorine-containing copolymer) The same manner as in Preparative Example 1 was repeated to give a fluorine-containing copolymer emulsion, except that the type and amount of the fluorine-free monomer and the acid group-containing monomer were changed. The composition of the monomers are shown in the following Table 3. Fluorine-containing monomer (structure a) Fluorine-free monomer Acid group-containing monomer Light Ester EH Light Ester S Light Ester PM 2-Acrylamido-2-methyl propane sulfonic acid Pre. Ex. 1 88 10 - 2 - Pre. Ex. 2 85 10 - 5 - Pre. Ex. 3 88 10 - - 2 Pre. Ex. 4 70 - 25 5 - Note: The indicated numeral value represents an amount in wt%. Example 1 of preparing fabric treated with metal salt 6-Nylon taffeta for a dyeing test was dipped in a 30°C aqueous solution (bath ratio 10:1) containing basic chromium sulfate (trade name: Baychrom F (manufactured by Bayer AG) in amount of 5 wt %, based on the test fabric weight, and rotary-treated by a dyeing test machine (manufactured by Tsujii Senki Kogyo Co., Ltd.) for 120 minutes, and then each of sodium formate and sodium hydrogen carbonate in an amount of 0.2 wt% based on the test fabric weight was added to conduct the neutralization. Then, the fabric was rotary-treated at 40°C for 20 minutes, hydro-extracted, washed with water, and dried at a room temperature to give a sample. Examples 1 to 4 Each of the fluorine-containing copolymer emulsions prepared in Preparative Examples 1 to 4 was diluted with the tap water to the solid content of 1 %. Then 3 % of isopropyl alcohol was added to give a treatment liquid. The test fabric prepared in Example 1 of preparing fabric treated with metal salt was dipped in said treatment liquid, and was squeezed with a mange to give a wet pickup of 25%. The test fabric was dried at 110°C for 3 minutes and thermally treated at 160°C for 1 minute. The water repellency and the oil repellency of the sample were measured before and after the ten times washing with water. The results are shown in Table 4. Comparative Examples 1-4 The same procedure as in Examples 1-4 was repeated, except that the 6-nylon taffeta for the dyeing test which was not applied to the metal salt treatment was used. The water repellency and the oil repellency of the sample were measured before and after the ten times washing with water. The results are shown in Table 4. Water repellency Oil repellency Ex. 1 100+ 6 80 2 Ex. 2 100+ 7 100 3 Ex. 3 100 6 50 2 Ex. 4 100+ 8 100 3 Com. Ex 1 50 5 0 0 Com. Ex. 2 50 5 0 0 Com. Ex. 3 0 0 0 0 Com. Ex. 4 100 5 50 0 Examples 5 and 6 The same process till the neutralization as in Example 1 of preparing test fabric treated with metal salt was repeated, and then the liquid was removed, the 6-nylon taffeta was dipped in a 50°C diluted liquid (bath ratio 10:1) containing 15 %, based on the test fabric weight, of the emulsion of Preparative Example 1 or 2 (corresponding to Example 5 and 6, respectively), and the rotary-treatment was conducted for 60 minutes. After 3 %, based on the test fabric weight, of formic acid was added, the rotary-treatment was conducted at 40°C for 20 minutes. After the liquid was removed, the fabric was washed with water, hydro-extracted, dried at 110°C for 3 minutes and thermally treated at 160°C for 1 minute. The water-repellency and the oil-repellency of the resultant sample were measured before and after the ten times of wash. The results of Examples 5 and 6 are shown in Table 5. Examples 7 and 8 A fluorine-containing water- and oil-repellent (Texguard TG-5431 manufactured by Daikin Industries Ltd.) was diluted with the tap water to the solid content of 1%, and 3% of isopropyl alcohol was added to give a treatment liquid. The test fabric prepared in each of Examples 5 and 6 was dipped in the treatment liquid, and squeezed with a mangle to give a wet pickup of 25%. The test fabric was dried at 110°C for 3 minutes and thermally treated at 160°C for 1 minute. The water repellency and the oil repellency of the resultant sample were measured before and after the ten times of wash. The results of Examples 7 and 8 are shown in Table 5. Comparative Example 5 A fluorine-containing water- and oil-repellent (Texguard TG-5431 manufactured by Daikin Industries Ltd.) was diluted with the tap water to the solid content of 1%, and 3 % of isopropyl alcohol was added to give a treatment liquid. An untreated 6-nylon taffeta for the dyeing test was dipped in the treatment liquid, and squeezed with a mange to give a wet pickup of 25%. The test fabric was dried at 110°C for 3 minutes and thermally treated at 160°C for 1 minute. The water repellency and the oil repellency of the resultant sample were measured before and after the ten times of wash. The results are shown in Table 5. Water repellency Oil repellency Ex. 5 100+ 6 100 3 Ex. 6 100+ 5 100 2 Ex. 7 100+ 6 100 3 Ex. 8 100+ 5 100 2 Com. Ex 5 100+ 6 80 0 Example 2 of preparing test fabric treated with metal salt The same procedure as in Example 1 of preparing test fabric treated with metal salt was repeated, except that basic zirconium sulfate (trade name: Zircotan (manufactured by Rohm & Haas Co.)) was used instead of basic chromium sulfate. Example 9 The same procedure as in Example 1 was repeated, except that the fluorine-containing copolymer emulsion prepared in Preparative Example 4 was used and the test fabric prepared in Example 2 of preparing test fabric treated with metal salt was used. The water repellency and the oil repellency of the sample were measured before and after the ten times of wash. The results are shown in Table 6. Water repellency Oil repellency Ex. 9 100+ 7 90 3 EFFECT OF THE INVENTION The present invention can give the excellent initial water- and oil-repellency to a textile, particularly a hydrophilic textile. In addition, the present invention can easily and stably give the permanent water- and oil-repellency which can endure a long-term use including the wash, the rubbing and like.

Claims: A method for treating a textile, comprising treating the textile with a salt of a metal having a valency of at least two and then treating the textile with a fluorine-containing polymer having a hydrophilic functional group, selected from a phosphoric acid group and a sulfonic acid group capable of coordinating with said metal. The method according to claim 1, wherein the metal having the valency of at least 2 is selected from the group consisting of chromium, titanium, zirconium and aluminum. The method according to claim 1, wherein the fluorine-containing polymer is a copolymer having a) a repeating unit derived from a fluorine-containing vinyl monomer, b) a repeating unit derived from an acid group-containing monomer of the formula: wherein R 1 is a hydrogen atom or a methyl group, R 2 is a non-substituted or substituted alkylene group having at most 6 carbon atoms, or a divalent group in which the above alkylene group is bonded to an ether group, an ester group, an amide group and the like, X is PO or SO 2 , M is a hydrogen atom or an alkaline metal atom, p is 1, n and m are 1 or 2 and n + m = 3 when X is PO, and p is 0 and n = m = 1 when X is -SO 2 -, and c) optionally present, a repeating unit derived from a fluorine-free monomer containing none of the phosphoric acid group and the sulfonic acid group; the total amount of the components b) and c) is at most 100 parts by weight per 100 parts by weight of the component a). A textile which is treated with the method according to claim 1. The textile according to claim 4, wherein a fiber of the textile is a polyamide or a polyester.

Inventors: ITAMI YASUO, KUBO MOTONOBU, MASUTANI TETSUYA, UESUGI NORIMASA, ITAMI, YASUO, KUBO, MOTONOBU, MASUTANI, TETSUYA, UESUGI, NORIMASA, ITAMI, YASUO, YODOGAWA WORKS OF DAIKIN IND. LTD., KUBO, MOTONOBU, YODOGAWA WORKS OF DAIKIN IND. LTD., MASUTANI, Tetsuya, Yodogawa Works of, UESUGI, Norimasa, Yodogawa Works of
Applicants: DAIKIN IND LTD, DAIKIN INDUSTRIES, LIMITED
Application year: 1994
Main classification: D06M15
IPC codes: D06M101, D06M15, D06M11